Siblings Always
by Skull1412
Summary: Kuroko, Nagisa, and Misaki are siblings and on an surprise meeting Kuroko and Misaki find out about the secret of Koro-sensei. Misaki is hiding a secret that could help 3-E greatly, will she show what it is? Misaki also founds about Karma's feelings for Nagisa as well, what will she do. Read to find out more on this crossover fanfiction!
1. Chapter 1

Chapter 1:

Kuroko was in the middle of lunch with the other freshman when he got a phone call. Everyone stared at Kuroko who had paled when he checked who had called. He stared at it for a second more before picking it up.

"Hello, this Kuroko." he said in a monotone.

" _Ah, Kuroko-kun, Misaki was admitted to the hospital again, she was in another car accident, there are no injuries for both driver and patient but she has a slight concussion, she should wake soon."_

Kuroko sighed in relieve, "Yes, thank you doctor, I'll go pick her up."

" _Ah no, Kuroko-kun, we will provide the transportation to drop her off at your school. Also, she keeps saying someone's name, I believe it's Nagisa, if you can, let her see this person please."_

"Very well, I can do that, is there anything else doctor?"

" _No that is all, Misaki will be at your school in 2 minutes, please meet her in the front."_

"Ok, thank you, and I will."

After that Kuroko ended the call and hurried to finish his lunch; which was bread and juice. Then he got up and was about to leave to go to the front.

"Wait! Kuroko, what was that call about? Where are you going? Who was on the phone? **Answer my question!** " Kagami said frustrated despite not letting Kuroko answer yet.

"Which one Kagami-kun? I need to go so please hurry."

"All of them!"

"But you said 'question' meaning a single question."

"Kuh! S-Shut up!"

"Very well, I will go now since you want me to be quiet."

"That's not what I-" Kagami couldn't finish because Kuroko disappeared.

" _ **KUROKO!"**_ Kagami yelled out but Kuroko was long gone.

Kuroko went outside and saw car pull up on the parking lot. The passenger door opened and girl about 5 years old with a large backpack came out. Once she saw Kuroko a smile spread on her face. As if contagious, Kuroko felt a smile form on his face too.

"Tetsu-nii!" the girl called out and ran toward Kuroko.

"Misaki-chan, are you ok?" Kuroko asked while picking her up and swinging her in a circle before settled her back down on the ground.

"I'm fine! The car only knocked me down, no injuries at all!" she said with a smile.

"If you say so Misaki-chan, what were you doing in the street anyways, you were supposed to be in class." Kuroko demanded.

"There was a kitty in the street, its leg was broken so I jump out of the window to get it but a car was driving and didn't see me." she explained and opened her backpack and a cat's head popped out.

"I see, next time be careful ok? You know misdirection makes people not be able to see you when you cross the street."

"I know Tetsu-nii; can we visit Shota-nii today? I haven't seen him since last week."

"Sure, we can visit afterschool, wait, doesn't Nagisa still have class though?"

"We can go surprise him! I haven't met his classmates or teachers yet! Actually, I haven't visited yours either, can I meet them too?!"

"Ok, well class is going to start soon, let's Misaki-chan."

"Ok!"


	2. Chapter 2

**Notice: I'm going on a 2 week trip, once I come back I shall update once again. I will not abandon this story.**

Chapter 2:

Class 3-E was having class without Koro-sensei who was in China, when a door slammed open.

"Shota-nii!" a girl's voice said.

Nagisa's head slipped from his hand when he heard the voice.

"M-Misaki-chan?!" he exclaimed when the teal haired girl came into view.

"Shota-nii! Long time no see!" she cheered and proceeded to run and tackle Nagisa.

"W-What are you doing here?!" he asked nervously, "Did Tetsu-nii bring you?"

"Yeah, he's here too!" Misaki said happily not noticing the questioning atmosphere in the class.

"I'm sorry for the intrusion." a male voice said.

Everyone swerved towards the voice and saw _**another**_ teal haired person.

Kuroko turned towards Misaki, "We have to talk to the teacher first Misaki." he scolded.

That was when the students tensed at the word teacher.

"I didn't see him when we came in though Tetsu-nii." Misaki pouted.

"Tetsu-nii, you're here too?!" Nagisa said with wide eyes.

Kuroko flashed Nagisa an apologetic smile, "Misaki got hit again and wanted to visit so I brang her here."

"Ah, so it happened again huh?" Nagisa sighed.

"Shota-nii, your hair is so long!" Misaki said as she ruffled through his hair.

Nagisa sighed louder this time.

"Is mother still on you?" Kuroko asked sympathetically.

"Yes she is, I wish she'd stop." Nagisa said, picked Misaki up and placed her on his lap.

"You can live with us Nagisa, you can still attend class here, our apartment isn't far from here." Kuroko offered.

"Really Tetsu-nii!" Nagisa perked up.

"Is Shota-nii gonna live with us?!" Misaki asked excited.

"If he agrees Misaki-chan." Kuroko said calmly with a smile.

" _Are they completely ignoring us?"_ Kayano whispered to Karma.

"They are." Karma said, not even whispering since he knew they heard them anyways.

"Sorry guys, these people are my siblings." Nagisa explained, "And Tetsu-nii, I want to live with you, I'll pack and leave a note for Mother before I leave."

"Leaving a note would be wise." Kuroko nodded in agreement.

"YAY! Shota-nii is staying with us!" Misaki cheered.

Kuroko's cellphone then rang.

"I wonder who it is…" Kuroko answered the phone call.

"KUROKO! YOU HAVE SOME NERVE SKIPPING OUT ON THE PRACTICE MATCH WITH SHUTOKU!" Riko screamed in anger.

Everyone in the classroom winced at the extremely loud voice.

"I'm sorry Riko-san, I brang my little sister to my little brother's school." Kuroko apologized.

"YOU HAVE A SISTER AND BROTHER?!" she screamed in shock this time.

"Yes I do Riko-san." Kuroko confirmed.

"WHY DIDN'T YOU TELL US?!" Riko scream once again.

"Riko-san, please lower your voice, I'm in a classroom. Also, I don't see why I should inform you of my private life." Kuroko said calmly.

"Ah, I'm sorry Kuroko-kun, but we would've liked to know if you had siblings to take care of." Riko said normally.

"You didn't ask." Kuroko deadpanned.

Misaki and Nagisa snickered; they've heard that phrase before.

"Are you going to come to the match or not?" Riko said irritated.

Kuroko glanced at Nagisa and mouthed, _'When does class end?'_

' _In 5 minutes.'_ Nagisa mouthed back.

"I'll be there in 8 minutes Riko-san, it takes a while to get there after all." Kuroko confirmed.

"Very well Kuroko-kun, we will hold out until then." Riko sighed.

"Thank you Riko-san." Kuroko said and ended the call.

"Oh? There are visitors?" a voice said.

Everyone swerved their heads to the voice and saw Koro-sensei.


	3. Chapter 3

**Chapter 3:**

"You must be the teacher, nice to meet you; my name is Kuroko Tetsuya, Nagisa's older brother." Kuroko said not affected that Koro-sensei was the biggest octopus in the world.

"Ah! You're the one at the candy store that had a fake wig, nose, and hands!" Misaki shouted in recognition.

"How did you know they were fake! My disguise was flawless!" Koro-sensei sweatdropped.

"Misaki is very observant and noticed that you didn't have a hairline, and your nose is a different color than your yellow skin, your gloves tend to slide down revealing your tentacles, and you don't have shoes but bigger tentacles instead." Misaki chirped.

"Koro-sensei got figured out by a kid." Kayano said dully.

"I knew the octopus couldn't disguise himself, it's so obvious." Terasaka snorted.

"T-That's not true! Koro-sensei is very good at disguising!" Koro-sensei panicked.

"Yeah right, by the way, class is over Koro-sensei." Fuwa said.

The class stood up and was about to walk out of the class when Koro-sensei blocked the entrance.

"Class won't be dismissed until you say Koro-sensei **IS** good at disguising!" Koro-sensei exclaimed.

" _Does he always do this Nagisa?"_ Kuroko whispered to Nagisa.

" _Yeah, it's because he doesn't want to be seen as a failure."_ Nagisa whispered back.

"Nagisa-kun please don't say such things about me! I am NOT a failure!" Koro-sensei yelled.

"Koro-sensei was it? I need to go now because my team is holding a practice match against Shutoku and I need to go now to play in the match." Kuroko asked politely.

"You're playing a match? I doubt you can play, most likely a benchwarmer." Terasaka snorted.

"I am a starter and I need to go before my coach kills me." Kuroko said.

"Let's go with him!" Kayano exclaimed, "It's been a while since I saw a basketball match."  
"Indeed, I want to see what this guy does, he could have a hidden talent like Nagisa." Karma said with a smirk.

' _It's like Akashi-kun is here, I wonder if they're cousins…'_ Kuroko wondered.

"Very well, class, let's go with Kuroko-san here to his match. Hustle students!" Koro-sensei ushered.

"Hey octopus!" Misaki yelled.

"Yes Misaki-chan?" Koro-sensei asked as he faced her.

"You're the one who the government is trying to kill right? The one who is going to blow up the Earth? But it's not true is it? You didn't blow up the moon did you? You can't stop yourself from blowing the Earth; your time is limited isn't it?" Misaki said seriously.

"How did you know?" Koro-sensei said with his face blank.

"I hacked into the military defense's information, but I did my own research and found out more than I was supposed to, actually Tetsu-nii helped me to find out too." Misaki shrugged.

"Tetsu-nii did?" Nagisa said with wide eyes.

"Well you were being secretive with your school time when we came to visit Nagisa, blame our curiosity, you have that problem too." Kuroko confessed.

"Well that explains why you weren't surprised when you saw Koro-sensei." Isogai said.

Kuroko was about to say something else when his phone rang. Kuroko paused when he was about to answer, already knowing who it was. He sighed, he was _**so**_ dead.

"Hello?" he said calmly, he wisely pulled the phone from his ear and put it at arm's length.

"KUROKO YOU IDIOT WHERE ARE YOU?! YOU SAID 8 MINUTES! IT'S ALREADY 10 MINUTES! IF YOU AREN'T HERE IN A MINUTE THEN I'LL QUADRUPLE YOUR TRAINING TOMORROW!" Riko yelled.

Kuroko didn't need to put it on speaker for the whole class to hear her voice.

"I'm sorry Riko-san, I got held up, I'm going now." Kuroko apologized when Riko was done yelling at him.

"Fine," Riko huffed, "Better hurry Kuroko-kun, we really need you right now."

"Very well Riko-san, please tell the team, 'Let's Have Some Fun!'" Kuroko said with a tiny smile.

"Kuroko, no way! That's my line!" Kiyoshi was faintly heard in the background.

"Ah, is it on speaker?" Kuroko asked with a knowing tone.

"Dammit Kuroko! You knew it was on speaker didn't you!" Kagami yelled.

"Maybe, maybe not Kagami-kun." Kuroko teased.

"Kuroko you better come over here or I'll hit you!" Hyuuga threatened.

"You sound like Kasamatsu-san now Hyuuga-sempai." Kuroko informed helpfully.

"You brat!" Hyuuga yelled.

"Clutch Time Captain? I'm so scared." Kuroko said, not sounding scared at all.

"Just get over here Kuroko-kun." Riko said quickly and ended the call before Hyuuga would break her phone.

Kuroko sighed, closed his phone, and looked at his siblings seriously. In his eyes they could tell that they should use their secret to get there in time.

"We better go now Nagisa, Misaki-chan. Koro-sensei; we will meet you over there ok?" Kuroko said hastily.

"We could go together Kuroko-san." Koro-sensei offered.

"No thanks octopus, you would slow us down." Misaki said as she stretched her limbs.

"is the cat in your backpack going to be ok Misaki-chan?" Kuroko asked her.

"Oh yeah, can you hold her?" Misaki handed the backpack to Kayano.

"Sure…" Kayano trailed off.

"Hurry up Misaki-chan, Tetsu-nii has to be there in less in a minute and we have 42 seconds left." Nagisa called as he and Kuroko went out the door to the outside.

The three stopped at the drop-off of the mountain and crouched down. The rest of the class stood in the back watching them with interest.

"On three." Nagisa said.

"THREE!" Misaki yelled and they were gone in an instant.

Karma, having keen eyes, saw three blurs for a millisecond; he automatically knew it was them. He smirked; Nagisa had such a secret, why he didn't show it in assassination was something he'd find out.

"Ok class; let's go as well, seeing as Nagisa and his siblings left us in the dust, we have to catch up as well, but on a bus." Koro-sensei clapped his tentacles.

The class agreed and started to go the fastest way down. Jumping down the mountain. When they reached the road, Karasuma-sensei and Bitch-sensei was already there; knowing everything from Koro-sensei who had visited them during the student's trip down the mountain and brang them there.


	4. Chapter 4

**Chapter 4:**

" _ **KU-RO-KO~"**_ Riko said slowly and dangerously, "YOU WERE 4 SECONDS LATE!"

Hyuuga sighed as he watched from the court as Riko put Kuroko in the Boston Crab Form. Kagami had cold sweat on his neck, that looked painful now that he looked closer at Kuroko.

"Hmph, that should teach Kuroko to not skip our practice match." Midorima scoffed.

"What Shin-chan means is that he's glad that Kuroko-chan is here since he wanted to impress him with his new move." Takao said happily before getting hit by a pineapple.

"Y-You idiot!" Midorima said with a scarlet blush on his face but didn't deny it with made Takao grin even though he was in pain.

Miyaji ran over, jumped, and kicked Takao's back, making Takao fall to the floor once again, "You imbecile! Don't just casually say that our ace got a new move! It was supposed to be a surprise!"

"Sorry sorry!" Takao laughed which was responded by his own coach throwing the pineapple this time, which made the players laugh slightly since he was the one who told them not to bring the pineapples.

"Nice to see you again Takao-chan." Kuroko said, popping out, Kuroko was squatting low, almost touching the floor with hands on his knees as he stared blankly at Takao.

"Hey Kuroko-chan, where's Misaki-chan and your other brother, Nagisa-chan right?" Takao asked nonchantly from the floor, "Kuroko-chan, lay on the floor with me, it's comfortable, so comfortable."

"They are at the bleachers, yes, and no." Kuroko commented.

"Eh? I forgot what I said, what does that mean?" Takao asked with his eyes closed as he practically became a pudding on the 'comfortable' floor.

"Get up Takao-chan, the floor is dirty." Kuroko sighed as he stood up.

"Ah~ Kuroko-chan is so tall now~" Takao commented.

Kuroko grew a tick mark and Ignite Pass Kai Takao on the floor, "Yes yes we all know I'm short, I change my mind, stay on the floor."

"Kuroko-chan is so mean!" Takao coughed as he clutched his stomach and curled into himself and let his tears fall.

"Tetsu-nii, don't you think that was a little too harsh?" Nagisa asked as he stared at the writhing figure on the floor in concern.

"Kazu-nii is used to it, don't worry." Misaki dismissed before skipping over to Takao and poked him while asking, "Kazu-nii do you have a lollipop?"

Takao popped back into life in a flash, "Of course Misaki-chan!"

Takao handed her a bright blue lollipop before striding over to Nagisa and produced a sparkling purple lollipop, "Hello! I'm Takao Kazunari, your siblings best friend and the person who comes in their house and eat their peanut butter at midnight!"

"Oh yeah, I need to buy more peanut butter." Kuroko exclaimed.

"KUROKO-CHAN YOU FORGOT THE PEANUT BUTTER?! THE STORE THAT SELLS THE BEST PEANUT BUTTER IS CLOSED ALREADY!" Takao screamed in horror, his soul flew out of his mouth and he landed on the floor in a cold white corpse.

"He did it again Tetsu-nii." Misaki commented like it was normal.

Kuroko had a mischievous glint in his eyes as he pulled out a trash bag and rope, "Well let's disposed of dear Takao-chan then."

" _ **KUROKO DON'T DO THAT!"**_


	5. Chapter 5

**Chapter 5:**

After a few arguments of whether or not to dispose of Takao who was still horrified that Kuroko had not bought peanut butter to satisfy him at night. Kuroko had lost the argument because he suggested setting Takao on fire which would help with their money since they kept on buying peanut butter for him every day.

"Kuroko-chan, were you serious when you said you would've burned me?" Takao asked after he came back to life and stood up.

"Yes." Kuroko said blankly.

"Eh?! Really?! You're kidding right?!" Takao exclaimed.

"I have no sense of humor Takao-chan." Kuroko reminded.

"Lies! You were the one who took Kagami's underpants and placed it on the flag pole in school during your practice!" Misaki exclaimed.

Everyone stared at Kuroko incredulously, Kuroko still had a blank face that gave away nothing but Nagisa saw the amusement in his eyes that gave him away.

"THAT WAS YOU KUROKO?!" Kagami shouted as he grabbed Kuroko's head in a vice grip.

"I don't know what you are talking about Kagami-kun, Misaki-chan made that up." Kuroko said with a monotone voice.

"You also placed that skunk prank on Mom." Misaki commented.

Nagisa choked before doubling over in surprise just as his classmates came into the gym, "YOU were the one who made Mom smell like a skunk for a month?! Tetsu-nii! She stank so bad that I couldn't even stay in the same room as her!"

"She deserved it; she threw a candy wrapper in the streets." Kuroko said, not even feeling a little bit sorry.

"Oh? A little mischievous prankster behind the polite face?" Karma asked with a bit of excitement.

"Karma! Don't encourage it!" Nagisa complained.

"But I'm a prankster too Nagisa, can't blame me." Karma reminded before turning to Kuroko, "Have you ever tried the wasabi prank?"

"I'm pretty sure the person I pulled that on went to the hospital soon after." Kuroko said and Karma grinned.

Karma slung an arm around Kuroko, "I think you and I are going get along just fine Kuroko."

"Same." Kuroko said bluntly but Karma saw the excitement in his eyes.

"TETSU-NII! KARMA!" Nagisa shouted incredulously but sighed in defeat.

"Poor Nagisa, you feeling left out? Don't worry; we'll include you in our pranks…on the other side that is." Karma said with a smirk.

"No way! Leave me out of it!" Nagisa shook his head frantically.

"Too bad, I have so many ideas already, hey Kuroko, let me stay over for a week, we can discuss so many things on pranks." Karma announced and Kuroko gave him his address.

"Don't give our address Tetsu-nii!" Nagisa yelled.

"Woah, calm down Nagisa, it can't be that bad." Sugino said, placing a hand on Nagisa's shoulder.

"You never seen Tetsu-nii in any other mood than blank so if his other side comes out, gotta hide for cover." Nagisa said nervously.

Sugino sweatdropped, it be that bad right? Apparently it could be because Karma already had blueprints thanks to Kuroko who pulled them out from nowhere. They had different materials out and were constructing one for a rotten egg prank that'll make the unlucky victim eat 20 rotten eggs before getting sprayed by rotten egg gas so bad that they'll smell like it for at least 3 months. Misaki made it worse saying she already had some rotten eggs in the basement for them to use.

"Ok, who's our unlucky victim?" Karma asked as they finished the plan.

"How that old geezer that keeps hitting the birds with rocks?" Misaki offered.

"Perfect, we'll put this plan in action tomorrow." Kuroko said, rolling the blueprint and placing it somewhere, not to be seen.

"Tetsu-nii, the match." Misaki helpfully added.

Everyone froze at the mention of the forgotten game; Riko grew a dark aura as she smiled a little too sweetly at Kuroko who had frozen up slightly. Takao had moved back with his hands clasped together in a prayer with tears streaming down his face, already ready for the death of Kuroko Tetsuya.

" _ **Kuroko-kun…"**_ Riko said slowly, with sweetness dripping down her words, coating over the promise of death in them.

"Yes Coach?" Kuroko said, trying not to show the fear as sweat formed on his neck as the rest of Seirin followed Takao's example and was getting ready for his death, Kiyoshi was already passing out funeral invitations with Izuki and Koganei while Hyuuga got the coffin ready with Tsuchida and Furihata, Kagami just looked at him with look like he was trying to memorize his face before death came.

Misaki teared up and handed him a slightly wilted flower, "Bye bye Tetsu-nii."

Kuroko looked at her before taking the flower and placing it on his ear before facing the angry coach who looked ready to pummel him with a blank look.


End file.
